SizeChangedLayoutNotifier class Null safety

A widget that automatically dispatches a SizeChangedLayoutNotification when the layout dimensions of its child change.

The notification is not sent for the initial layout (since the size doesn't change in that case, it's just established).

To listen for the notification dispatched by this widget, use a NotificationListener<SizeChangedLayoutNotification>.

The Material class listens for LayoutChangedNotifications, including SizeChangedLayoutNotifications, to repaint InkResponse and InkWell ink effects. When a widget is likely to change size, wrapping it in a SizeChangedLayoutNotifier will cause the ink effects to correctly repaint when the child changes size.

See also:

  • Notification, the base class for notifications that bubble through the widget tree.
Inheritance

Constructors

SizeChangedLayoutNotifier({Key? key, Widget? child})
Creates a SizeChangedLayoutNotifier that dispatches layout changed notifications when child changes layout size.
const

Properties

child → Widget?
The widget below this widget in the tree.
finalinherited
hashCode → int
The hash code for this object.
nonVirtual">@nonVirtualread-onlyinherited
key → Key?
Controls how one widget replaces another widget in the tree.
finalinherited
runtimeType → Type
A representation of the runtime type of the object.
read-onlyinherited

Methods

createElement() → SingleChildRenderObjectElement
RenderObjectWidgets always inflate to a RenderObjectElement subclass.
inherited
createRenderObject(BuildContext context) → RenderObject
Creates an instance of the RenderObject class that this RenderObjectWidget represents, using the configuration described by this RenderObjectWidget.
override
debugDescribeChildren() → List<DiagnosticsNode>
Returns a list of DiagnosticsNode objects describing this node's children.
protected">@protectedinherited
debugFillProperties(DiagnosticPropertiesBuilder properties) → void
Add additional properties associated with the node.
inherited
didUnmountRenderObject(covariant RenderObject renderObject) → void
A render object previously associated with this widget has been removed from the tree. The given RenderObject will be of the same type as returned by this object's createRenderObject.
protected">@protectedinherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a non-existent method or property is accessed.
inherited
toDiagnosticsNode({String? name, DiagnosticsTreeStyle? style}) → DiagnosticsNode
Returns a debug representation of the object that is used by debugging tools and by DiagnosticsNode.toStringDeep.
inherited
toString({DiagnosticLevel minLevel = DiagnosticLevel.info}) → String
A string representation of this object.
inherited
toStringDeep({String prefixLineOne = '', String? prefixOtherLines, DiagnosticLevel minLevel = DiagnosticLevel.debug}) → String
Returns a string representation of this node and its descendants.
inherited
toStringShallow({String joiner = ', ', DiagnosticLevel minLevel = DiagnosticLevel.debug}) → String
Returns a one-line detailed description of the object.
inherited
toStringShort() → String
A short, textual description of this widget.
inherited
updateRenderObject(BuildContext context, covariant RenderObject renderObject) → void
Copies the configuration described by this RenderObjectWidget to the given RenderObject, which will be of the same type as returned by this object's createRenderObject.
protected">@protectedinherited

Operators

operator ==(Object other) → bool
The equality operator.
nonVirtual">@nonVirtualinherited